Northwest Africa 11195 (NWA 11195)

(Northwest Africa)

Purchased: 2015

Classification: Iron meteorite (IAB-MG)

Petrography: Bandwidth is ~1.8 mm, corresponding to a coarse octahedrite. Very little taenite, present at some, not all, kamacite-kamacite boundaries and in uncommon plessite fields; no troilite is visible. There are a few small (~3 × ~1 mm) hieroglyphic schreibersites and many tiny rhabdites. Sample has a thin (0.3-0.5 mm) weathering rind. It seems to show a reheated zone with splotchy dark areas extending in ~2 mm from weathering rind. This zone may reflect reheating after the fall.

Geochemistry: Composition: Co, 4.52 mg/g; Ni, 70.1 mg/g; Ga, 89.9 μg/g; Ge, 435.0; As, 11.6 μg/g; W, 1.26 μg/g; Ir 2.62 μg/g; Au, 1.474 μg/g. The meteorite is compositionally a member of IAB-MG. Its composition is relatively close to that of the NWA 854 shower. The Ir in this meteorite is 2.62 μg/g, that in NWA 854 is 2.10 (based on three different specimens). Such a large range is seen in Canyon Diablo and Campo del Cielo, but it may be an independent fall.

Classification: The meteorite is a IAB-MG based on composition and structure.